What the evidence says. Several controlled trials; effects real but modest or context-dependent.
What is Molybdenum?
Molybdenum is a mineral used for corrects rare deficiency: reverses sulfur-amino-acid intolerance, tachycardia and neurologic symptoms in patients on long-term molybdenum-free parenteral nutrition (single documented case, resolved with iv molybdate). NutriDex grades the human evidence as Moderate. Molybdenum is an essential trace mineral that, as the molybdopterin cofactor, enables four enzymes—sulfite oxidase, xanthine oxidase, aldehyde oxidase, and mARC—most critically detoxifying sulfite from sulfur-amino-acid metabolism. True dietary deficiency is essentially unknown in free-living people; the only documented case occurred during prolonged molybdenum-free parenteral nutrition, and the inborn molybdenum cofactor deficiency (a genetic, not dietary, disorder) causes fatal neonatal neurodegeneration treatable only with fosdenopterin, not dietary molybdenum. Controlled depletion studies show humans stay in balance on as little as ~22 mcg/day, so the typical diet vastly exceeds needs. There are no credible RCTs showing benefit from molybdenum supplements in non-deficient people; supplementation should be regarded as correcting a (rare) deficiency rather than improving health.
Purported Benefits
✓Corrects rare deficiency: reverses sulfur-amino-acid intolerance, tachycardia and neurologic symptoms in patients on long-term molybdenum-free parenteral nutrition (single documented case, resolved with IV molybdate)
✓Essential cofactor for sulfite oxidase—prevents accumulation of toxic sulfite/S-sulfocysteine from cysteine and methionine metabolism
✓Cofactor for xanthine oxidase—required for purine catabolism and uric acid formation
✓Cofactor for aldehyde oxidase and mARC—participates in metabolism of aldehydes, certain drugs, and detoxification of N-hydroxylated compounds
✓Higher molybdenum status is associated (observational, not causal) with lower serum uric acid and reduced hyperuricemia/gout prevalence in NHANES
✓No demonstrated benefit of supplementation in people who already meet intake (the overwhelming majority)
Evidence by outcome
The same supplement can be well-proven for one use and unproven for another — here is the human evidence graded outcome by outcome.
Adult RDA (US): 45 mcg/day for men and women (pregnancy/lactation 50 mcg/day). EFSA sets an Adequate Intake of 65 mcg/day for adults. Typical Western intakes (~75-250 mcg/day) already exceed needs, and balance is maintained at ~22 mcg/day. Supplement doses are usually small (45-100 mcg). Tolerable Upper Intake Level (UL): 2,000 mcg (2 mg)/day for adults.
Active Compounds
Supplement forms: sodium molybdate, ammonium molybdate, molybdenum glycinate/chelate (in some multivitamins/trace-element mixes)Pharmaceutical: ammonium tetrathiomolybdate (investigational copper-lowering agent, NOT a nutritional supplement)Dietary sources: legumes (beans, lentils, peas) are the richest sourceWhole grains, nuts, and seedsOrgan meats (liver) and dairyLeafy greens; content varies with soil molybdenum and water
Safety & Cautions
⚠
Low toxicity at dietary levels; deficiency is essentially nonexistent outside parenteral nutrition, so routine supplementation is unnecessary. UL is 2,000 mcg/day, derived largely from animal reproductive/growth toxicity (human data are limited). Very high occupational and dietary exposures have been linked to gout-like syndromes and elevated uric acid in some reports, consistent with molybdenum's role in xanthine oxidase. The major interaction is with COPPER: molybdenum (especially as tetrathiomolybdate) antagonizes copper absorption and bioavailability—this is exploited therapeutically to lower copper in Wilson disease, but means high molybdenum intake can theoretically worsen copper status. Molybdenum cofactor deficiency is a genetic enzyme-synthesis disorder that does NOT respond to dietary molybdenum and requires fosdenopterin (cyclic pyranopterin monophosphate). No important drug interactions are established at nutritional doses. Educational only — always check with your doctor or pharmacist before combining Molybdenum with any medicine.
Molybdenum is most often taken for Corrects rare deficiency: reverses sulfur-amino-acid intolerance, tachycardia and neurologic symptoms in patients on long-term molybdenum-free parenteral nutrition (single documented case, resolved with IV molybdate), Essential cofactor for sulfite oxidase—prevents accumulation of toxic sulfite/S-sulfocysteine from cysteine and methionine metabolism, Cofactor for xanthine oxidase—required for purine catabolism and uric acid formation, Cofactor for aldehyde oxidase and mARC—participates in metabolism of aldehydes, certain drugs, and detoxification of N-hydroxylated compounds. The sulfite-clearing cofactor metal you almost never run short on
Does Molybdenum work — what does the evidence say?
Moderate evidence. Several controlled trials; effects real but modest or context-dependent. Molybdenum is an essential trace mineral that, as the molybdopterin cofactor, enables four enzymes—sulfite oxidase, xanthine oxidase, aldehyde oxidase, and mARC—most critically detoxifying sulfite from sulfur-amino-acid metabolism. True dietary deficiency is essentially unknown in free-living people; the only documented case occurred during prolonged molybdenum-free parenteral nutrition, and the inborn molybdenum cofactor deficiency (a genetic, not dietary, disorder) causes fatal neonatal neurodegeneration treatable only with fosdenopterin, not dietary molybdenum. Controlled depletion studies show humans stay in balance on as little as ~22 mcg/day, so the typical diet vastly exceeds needs. There are no credible RCTs showing benefit from molybdenum supplements in non-deficient people; supplementation should be regarded as correcting a (rare) deficiency rather than improving health.
What is the typical dose of Molybdenum?
Adult RDA (US): 45 mcg/day for men and women (pregnancy/lactation 50 mcg/day). EFSA sets an Adequate Intake of 65 mcg/day for adults. Typical Western intakes (~75-250 mcg/day) already exceed needs, and balance is maintained at ~22 mcg/day. Supplement doses are usually small (45-100 mcg). Tolerable Upper Intake Level (UL): 2,000 mcg (2 mg)/day for adults.
Is Molybdenum safe? Any cautions or side effects?
Low toxicity at dietary levels; deficiency is essentially nonexistent outside parenteral nutrition, so routine supplementation is unnecessary. UL is 2,000 mcg/day, derived largely from animal reproductive/growth toxicity (human data are limited). Very high occupational and dietary exposures have been linked to gout-like syndromes and elevated uric acid in some reports, consistent with molybdenum's role in xanthine oxidase. The major interaction is with COPPER: molybdenum (especially as tetrathiomolybdate) antagonizes copper absorption and bioavailability—this is exploited therapeutically to lower copper in Wilson disease, but means high molybdenum intake can theoretically worsen copper status. Molybdenum cofactor deficiency is a genetic enzyme-synthesis disorder that does NOT respond to dietary molybdenum and requires fosdenopterin (cyclic pyranopterin monophosphate). No important drug interactions are established at nutritional doses.
How many studies support Molybdenum?
NutriDex cites 9 sources for Molybdenum, graded "Moderate".
Cite this page
APA
Peh, D. (2026). Molybdenum: Benefits, Dosage, Side Effects & Evidence. NutriDex — The Supplement Research Compendium. Retrieved 16 Sept 2026, from https://nutridex.info/s/molybdenum
BibTeX
@misc{nutridex_molybdenum,
author = {Peh, Daryl},
title = {Molybdenum: Benefits, Dosage, Side Effects \& Evidence},
year = {2026},
howpublished = {NutriDex --- The Supplement Research Compendium},
url = {https://nutridex.info/s/molybdenum},
note = {Reviewed by Dr Daryl Peh, MBBS Singapore, MMed FM. Accessed 2026-09-16}
}
For medical claims, citing the underlying primary studies linked above is preferred. NutriDex is an educational reference, not medical advice.